Randomised controlled trial: susceptibility-guided therapy versus empiric bismuth quadruple therapy for first-line Helicobacter pylori treatment

Role of MIC levels and 23S rRNA mutation sites to clarithromycin in 14-day clarithromycin bismuth quadruple therapy for Helicobacter pylori eradication: A prospective trial in Beijing

Background

Rising clarithromycin resistance undermines Helicobacter pylori (H. pylori) treatment efficacy. We aimed to determine clarithromycin's minimum inhibitory concentration (MIC) levels and identify specific mutation sites in the 23S ribosomal subunit (23S rRNA) that predict treatment outcomes in a 14-day regimen of clarithromycin bismuth quadruple therapy (amoxicillin 1g, clarithromycin 500 mg, rabeprazole 10 mg, and colloidal bismuth pectin 200 mg).

Materials and methods

We included adult H. pylori patients who hadn't previously undergone clarithromycin-based treatment, either as initial or rescue therapy. Exclusions were made for penicillin allergy, recent use of related medications, severe illnesses, or inability to cooperate. Patients underwent a 14-day clarithromycin bismuth quadruple therapy. Gastric mucosa specimens were obtained during endoscopy before eradication. MIC against amoxicillin and clarithromycin was determined using the E-test method. The receiver operating characteristic (ROC) curve helped to find the optimal clarithromycin resistance MIC breakpoint. Genetic sequences of H. pylori 23S rRNA were identified through Sanger Sequencing. (ChiCTR2200061476).

Results

Out of 196 patients recruited, 92 met the inclusion criteria for the per-protocol (PP) population. The overall intention-to-treat (ITT) eradication rate was 80.00 % (84/105), while the modified intention-to-treat (MITT) and PP eradication rates were 90.32 % (84/93) and 91.30 % (84/92) respectively. No amoxicillin resistance was observed, but clarithromycin resistance rates were 36.19 % (38/105), 35.48 % (33/93), and 34.78 % (33/92) in the ITT, MITT, and PP populations respectively. Compared with the traditional clarithromycin resistance breakpoint of 0.25 μg/mL, a MIC threshold of 12 μg/mL predicted better eradication. Among 173 mutations on 152 sites in the 23S rRNA gene, only the 2143A > G mutation could predict eradication outcomes (p < 0.000).

Conclusions

Interpretation of elevated MIC values is crucial in susceptibility testing, rather than a binary "susceptible" or "resistant" classification. The 2143A > G mutation has limited specificity in predicting eradication outcomes, necessitating further investigation into additional mutation sites associated with clarithromycin resistance.

Clarifying varied Helicobacter pylori eradication therapies: A comprehensive review

Current global variations exist in Helicobacter pylori (H. pylori) eradication regimens. Triple therapy (TT), bismuth quadruple therapy (BQT), and high-dose dual therapy (HDDT) currently represent the predominant regimens. These regimens diverge in terms of treatment duration, the utilization of susceptibility testing, acid-inhibiting drug administration, and patient education. We conducted a comprehensive systematic literature review on these H. pylori treatment regimens. Our review aims to provide standardized treatment recommendations for H. pylori, reducing the risk of amalgamating findings from diverse eradication regimens. Recent research suggests that the optimal treatment duration for TT and BQT may be 14 and 10 days, respectively. Selecting the appropriate treatment duration for HDDT should rely on regional research evidence, and 14 days may be the optimal duration. The incorporation of susceptibility testing in TT is of paramount importance. In the case of BQT, the absence of susceptibility testing may be considered as an option, contingent upon cost and availability, and should be determined based on local antibiotic resistance patterns and the efficacy of empirical regimens. The type and dosage of acid-inhibiting drug would affect the efficacy of these regimens. Acid-inhibiting drugs should be selected and applied reasonably according to the population and therapies. Adequate patient education plays a pivotal role in the eradication of H. pylori. In regions with accessible local research evidence, the 10-day empirical BQT regimen may be considered a preferred choice for H. pylori eradication.

Global research trends and hotspots of Helicobacter pylori eradication based on clinical trial registration platforms: A cross-sectional analysis

BACKGROUND

This study aimed to obtain an overview of clinical trials on Helicobacter pylori (H. pylori) eradication and analyze the global trends and hotspots in this field.

METHODS

We collected the data from clinical trials focused on H. pylori eradication in the primary clinical trial registries from 2000 to 2022 in the world. Then we analyzed the research trends and hotspots in H. pylori eradication regimens in different regions at different periods.

RESULTS

A total of 780 clinical trials were included, which were mainly conducted in Asia (682), followed by Europe (59), Africa (20), North America (16), South America (7), Oceania (2). The most active countries were China (343), Iran (140), South Korea (63), and Japan (73). "Bismuth-containing quadruple therapy (BQT)" was the most studied regimen (159, 20.38 %). Additionally, clinical trials focused on potassium-competitive acid blockers (P-CABs)-based therapy, probiotics, and high-dose dual therapy (HDDT) were constantly increasing. BQT received the most attention in China (26.53 %) and Iran (22.14 %), while it was tailored therapy in South Korea (23.29 %). P-CABs-based therapy was the main reseach hotspot in Japan (61.90 %).

CONCLUSION

How to eradicate H. pylori infection has been a heated research topic. BQT, P-CABs-based therapy, probiotics, and HDDT attracted the most attention in recent years.

Optimizing Helicobacter pylori Treatment: An Updated Review of Empirical and Susceptibility Test-Based Treatments

As the rate of discovery of drug-resistant Helicobacter pylori cases increases worldwide, the relevant societies have updated their guidelines for primary eradication regimens. A promising strategy against drug-resistant H. pylori is tailored therapy based on the results of an antibiotic susceptibility test; however, it is difficult to apply this strategy to all cases. Although culture-based antibiotic susceptibility tests can assess resistance to any antimicrobial agent, their greatest disadvantage is the time required to draw a conclusion. In contrast, molecular-based methods, such as polymerase chain reaction, can rapidly determine the presence of resistance, although a single test can only test for one type of antimicrobial agent. Additionally, the limited availability of facilities for molecular-based methods has hindered their widespread use. Therefore, low-cost, minimally invasive, simple, and effective primary regimens are needed. Several studies have compared the efficacy of the latest primary eradication regimens against that of tailored therapies, and their results have shaped guidelines. This article reviews the latest research on empirical and tailored treatments for H. pylori infections. Evidence for the superiority of tailored therapy over empirical therapy is still limited and varies by region and treatment regimen. A network meta-analysis comparing different empirical treatment regimens showed that vonoprazan triple therapy provides a superior eradication effect. Recently, favorable results towards vonoprazan dual therapy have been reported, as it reached eradication levels similar to those of vonoprazan triple therapy. Both vonoprazan dual therapy and tailored therapy based on antibiotic susceptibility tests could contribute to future treatment strategies.

Empirical versus tailored therapy based on genotypic resistance detection for Helicobacter pylori eradication: a systematic review and meta-analysis

Background

The eradication rate of Helicobacter pylori infection with empirical therapy has decreased due to increased drug resistance. The latest guidelines recommend genotypic resistance-guided therapy, but its clinical efficacy remains unclear.

Objectives

The purpose of our study was to evaluate whether tailored therapy based on genotypic resistance is superior to empirical therapy for H. pylori infection.

Design

A systematic review and meta-analysis of randomized controlled trials (RCTs) comparing tailored therapy based on genotypic resistance with empirical therapy was performed.

Sources and methods

We retrieved relevant studies from PubMed, Embase, and the Cochrane Library. The primary outcome was H. pylori eradication rate and the adverse events (AEs) was the secondary outcome. A random-effect model was applied to compare pooled risk ratios (RRs) with related 95% confidence intervals (CIs).

Results

A total of 12 qualified RCTs containing 3940 patients were identified in our systematic review and meta-analysis. The pooled eradication rates of tailored therapy based on the detection of genotypic resistance were consistently higher than those in the empirical treatment group, with no statistical significance. In triple therapy, the eradication rate was significantly higher in the tailored group than in the empirical group by intention-to-treat analysis (ITT) and per-protocol analysis (PP) analysis (p < 0.0001, RR: 1.20; 95% CI: 1.12-1.29; p < 0.0001, RR: 1.20; 95% CI: 1.15-1.25). In quadruple therapy, the eradication rate was higher in the empirical group (p = 0.001, RR: 0.93; 95% CI: 0.89-0.97; p = 0.009, RR: 0.95; 95% CI: 0.92-0.99). And this result was true for both bismuth quadruple therapy (BQT) and non-BQT. Regarding total AEs, the pooled rate was 34% in the tailored group and 37% in the empirical group, and no difference between the two groups was found (p = 0.17, RR: 0.88; 95% CI: 0.74-1.06).

Conclusion

In conclusion, tailored therapy based on molecular methods may offer better efficacy than empirical triple therapy, but it may not be superior to empirical quadruple therapy in eradicating H. pylori infection. Larger and more individualized RCTs are needed to aid clinical decision-making.

Registration PROSPERO

CRD42023408688.

Comparison of Risk and Severity of Helicobacter Pylori Infection in Non-Native Versus US Native Pediatric Patients

Introduction

Helicobacter pylori (HP) infection is associated with gastritis, peptic ulcer disease (PUD) in the stomach and duodenum, and an increased risk of gastric cancer. The risk of infection, secondary symptoms, and negative outcomes is known to be increased in low- and middle-income countries and vastly less substantial in the United States and Europe. Current North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines recommend endoscopic diagnosis and susceptibility-guided therapy, which is not reflected by current adult guidelines for therapy. In this study, we complete a single-center retrospective review of HP risk by nativity status, as well as the results of the use of standard empiric therapy in HP and PUD patients.

Methods

We retrospectively reviewed all endoscopies with patients aged 1-21 years with a known nativity status and identified all HP diagnoses. We also completed the classification of Kyoto scores and classified patients as gastritis versus PUD. Treatment records were obtained, as well as downstream documentation of the impact of empiric therapy. HP prevalence and severity were compared between non-native and native US populations.

Results

In total 332 patients were identified, with 59 HP diagnoses. However, 64 patients were immigrants, and 268 were US natives. Totally 39.1% of all immigrant patients had an endoscopically identified HP infection, compared to only 12.7% of US native patients (P < 0.01, relative risk 3.07). HP severity was worse in immigrant patients (Kyoto score 1.5 versus 0.89; P = 0.008). Empiric high-dose amoxicillin triple therapy was equally effective in reducing symptoms in gastritis versus PUD patients.

Conclusions

Immigrant patients have a substantially higher risk and severity of HP infection than US natives. Empiric therapy remains highly effective at relieving symptoms. These findings in aggregate suggest that North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines may not adequately serve non-native pediatric patients, with an additional prospective multicenter study needed to confirm. In addition, a prospective study of treatment based on stool antigen tests, as well as a larger prospective study of empiric therapy, may suggest alterations to our approach in line with recent changes to adult Gastroenterology practice.

Efficacy of quadruple therapy with clarithromycin based on faecal molecular antimicrobial susceptibility tests as first-line treatment for Helicobacter pylori infection: a protocol of a single-centre, single-blind, randomised clinical trial in China

INTRODUCTION

Helicobacter pylori is the most well-known risk factor for gastric cancer. Antibiotic resistance is the main reason for the failure of H. pylori eradication, and understanding the antibiotic resistance before treatment may be the main determinant of successful eradication of H. pylori. This study aims to evaluate the efficacy and safety of quadruple therapy based on faecal molecular antimicrobial susceptibility tests for the first-line eradication of H. pylori infection.

METHODS AND ANALYSIS

This is a single-centre, single-blind, randomised controlled trial, enrolling 855 patients with H. pylori infection. Patients are randomised to three groups for a 14-day treatment: group A: amoxicillin- and clarithromycin-based bismuth-containing quadruple therapy (BQT) (rabeprazole 10 mg, amoxicillin 1 g, clarithromycin 500 mg and colloidal bismuth 200 mg two times per day); group B: clarithromycin medication history-based BQT (rabeprazole 10 mg, amoxicillin 1 g, furazolidone 100 mg (with clarithromycin medication history)/clarithromycin 500 mg (without clarithromycin medication history) and colloidal bismuth 200 mg two times per day); group C: antimicrobial susceptibility test-based BQT (rabeprazole 10 mg, amoxicillin 1 g, clarithromycin 500 mg (clarithromycin-sensitive)/furazolidone 100 mg (clarithromycin resistant) and colloidal bismuth 200 mg two times per day). The primary end point is the eradication rate. The secondary end points are the incidence of adverse events and compliance.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Second Affiliated Hospital, School of Medicine, Zhejiang University (Number 20230103). The results will be published in the appropriate peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT05718609.

Advances in the pharmacological and regulatory management of multidrug resistant Helicobacter pylori

INTRODUCTION

Antibiotic resistance of Helicobacter pylori (H. pylori) hampers the success of eradication and in recent years multidrug resistance (MDR) shows an increase worldwide.

AREAS COVERED

This review covers current aspects of pharmacological and regulatory management of MDR-resistant H. pylori infection.

EXPERT OPINION

MDR H. pylori is increasing worldwide and its prevalence varies both between continents and countries. High consumption and misuse of antibiotics, H. pylori treatment failures and bacterial factors such as mutations, efflux pumps and biofilms are among the factors associated with MDR. Important steps for confronting the rise of MDR H. pylori strains should follow the principles of antibiotic stewardship, i.e. eradication regimens should be optimized with regard to all aspects of therapy, including drugs, doses, formulation, frequency of administration, administration in relation to meals and duration of therapy that reliably achieve at least 90% (preferably >95%) cure rates in adherent patients with susceptible infections.

Susceptibility-guided sequential strategy versus empirical therapy for Helicobacter pylori infection: study protocol for a randomised controlled trial

BACKGROUND

New treatment strategies are required against infections caused by Helicobacter pylori, which grows increasingly resistant to antibiotics. Polymerase chain reaction-based methods for antibiotic susceptibility testing are available for detecting H. pylori-specific mutations that confer resistance to clarithromycin and levofloxacin. Several meta-analyses have compared eradication rates for susceptibility-guided versus empirical therapy for H. pylori treatment; however, all have significant limitations and high heterogeneity, and the results are contradictory. The main objective of this trial is to assess whether a sequential strategy based on molecular susceptibility testing-guided therapy for H. pylori has a better eradication rate than empirical therapy.

METHODS

This trial is designed as a prospective, randomised, open-label, active-controlled and single-centre study. Men and women who are H. pylori-positive, naïve to treatment, and aged 18-65 years will be recruited. A total of 500 participants will be randomised to receive either empirical therapy or a susceptibility-guided sequential strategy. Bismuth quadruple therapy will be the empirical first-line therapy, and in case of failure, high-dose dual (proton-pump inhibitor + amoxicillin) treatment will be the rescue therapy. For the susceptibility-guided sequential strategy, regimen selection will be based on H. pylori susceptibility to clarithromycin (first-line) and levofloxacin (rescue). A first-line treatment of clarithromycin triple therapy will be selected for clarithromycin-sensitive strains. For clarithromycin resistance, a high-dose dual therapy will be selected. During the rescue treatment, a levofloxacin quadruple regimen will be selected for levofloxacin-sensitive strains, and a furazolidone quadruple regimen will be selected for others. The primary outcome is the first-line eradication rate in both groups, and the overall (including first and rescue therapies) H. pylori eradication rate in both groups is one of the secondary outcomes. The eradication rates of H. pylori will be analysed by intention-to-treat analysis, modified intention-to-treat analysis, and per-protocol analysis.

DISCUSSION

This randomised controlled trial will provide objective and valid evidence about the value of polymerase chain reaction-based molecular methods for antibiotic susceptibility testing in guiding H. pylori eradication.

TRIAL REGISTRATION

Clinicaltrials.gov NCT05549115. Released on 18 September 2022. First posted on 22 September 2022. Enrolment of the first participant on 20 September 2022. The study is retrospectively registered.

Egg yolk antibody combined with bismuth-based quadruple therapy in Helicobacter pylori infection rescue treatment: a single-center, randomized, controlled study

Background

The increasing antibiotic resistance is the main issue causing Helicobacter pylori (H. pylori) eradication failure. As a nutritional supplement, Egg Yolk Antibody (Ig Y) provides a new approach for H. pylori infection rescue therapy.

Methods

In this randomized, controlled study, 100 H. pylori-positive patients with previous H. pylori eradication treatment were included. All individuals received standard bismuth-containing quadruple therapy twice daily (5 mg ilaprazole, 100 mg doxycycline, 500 mg clarithromycin or 1 g amoxicillin or 100 mg furazolidone, and 220 mg colloidal bismuth tartrate) for 14 days and were randomized to receive either twice daily 7 g Ig Y-H. pylori treatment (study group) or not (control group). 4 weeks after the end of treatment, urea breath tests were used to assess the H. pylori eradication rate. All participants scored by the Global Overall Symptom scale (GOS) and recorded adverse events during the trial.

Results

The H. pylori eradication rates were 84.0% (95% CI 73.5-94.5%) vs. 80.0% (95% CI 68.5-91.5%) in the study and control groups at intention-to-treat (ITT) analysis and 85.7% (95% CI 75.6-95.9%) vs. 80.0% (95% CI 68.5-91.5%) at per-protocol (PP) analysis, respectively. The number of over 80% symptom relief after treatment in the two groups was 27 (60%) and 12 (29.2%) (p < 0.05), and the incidences of adverse events were 4 (8%) and 6 (12%), respectively.

Conclusion

Both groups achieved satisfactory eradication efficiency in H. pylori rescue therapy and Ig Y-H. pylori effectively alleviates the symptoms with good compliance and fewer adverse effects.

Antibiotic resistance characteristics and risk factors analysis of Helicobacter pylori strains isolated from patients in Liaoning Province, an area in North China

Background

The prevalence of Helicobacter pylori (H. pylori) keeps rising while the eradication rate continues to decline due to the increasing antibiotic resistance. Regional variations of antimicrobial resistance to H. pylori have been recommended by guidelines in recent years. This study aims to investigate the antibiotic resistance rate of H. pylori and its association with infected subjects' characteristics in Liaoning Province, an area in north China.

Methods

Gastric tissues from 178 H. pylori positive participants without previous antibiotic use within four weeks were collected for H. pylori culture. Antibiotic susceptibility to furazolidone (AOZ), tetracycline (TC), levofloxacin (LFX), metronidazole (MET), clarithromycin (CLA), and amoxicillin (AMX) were examined with the agar dilution method. Associations between H. pylori resistance and patient characteristics were further analysed.

Results

No resistance was observed in AOZ or TC. For LFX, MET, CLA, and AMX, the overall resistance rates were 41.10%, 79.14%, 71.78%, and 22.09% respectively. There were significant differences between resistance to CLA and MALToma (P = 0.021), and between resistance to MET and age (P < 0.001).

Conclusions

The primary resistant rates of LEX, MET, CLA, and AMX were relatively high in Liaoning. Treatment effectiveness improvement could be achieved by prior antimicrobial susceptibility tests before antibiotic prescription.

Efficacy of tegoprazan-based bismuth quadruple therapy compared with bismuth quadruple therapy for Helicobacter pylori infection: A randomized, double-blind, active-controlled study

BACKGROUND

Bismuth-based quadruple therapy (BQT) is recommended as the first-line empirical therapy for Helicobacter pylori eradication as it is not associated with resistance. However, few studies have investigated the use of potassium-competitive acid blockers for BQT.

AIM

To investigate the efficacy and safety profiles of tegoprazan-based BQT (TBMT) versus lansoprazole-based BQT (LBMT) for H. pylori eradication.

METHODS

We included patients older than 18 with an H. pylori infection without a history of H. pylori eradication who visited four university-affiliated hospitals between March 2020 and December 2021. H. pylori infection was diagnosed using a rapid urease test or Giemsa staining. Patients were randomly assigned to the TBMT or LBMT group.

RESULTS

217 subjects were randomly allocated to receive either TBMT (n = 108) or LBMT (n = 109) therapy. Intention-to-treat (ITT) eradication rates of TBMT and LBMT were 80.0% and 77.4% (95% confidence interval [CI]: -8.4 to 13.7, p = 0.0124), respectively. Corresponding modified ITT rates were 90.3% and 84.5% (95% CI: -3.6 to 15.2, p = 0.0005), respectively. Per-protocol (PP) eradication rates of TBMT and LBMT were 90.2% and 82.4% (95% CI: -2.5 to 18.2, p = 0.0003), respectively. There was no significant difference in the rate of adverse events between the TBMT and LBMT groups (39.1% vs. 43.4%, p = 0.5211). TBMT showed higher eradication rates than that of LBMT in ITT, m-ITT, and PP analysis.

CONCLUSION

TBMT showed a noninferior eradication rate and similar adverse events to LBMT as a first-line eradication regimen. Our results suggest that tegoprazan might be substituted for proton pump inhibitors in H. pylori eradication regimens.

Current role of tailored therapy in treating Helicobacter pylori infections. A systematic review, meta-analysis and critical analysis

BACKGROUND AND AIMS

Recent guidelines dictate that all Helicobacter pylori (H. pylori) infected subjects should receive curative therapy. The efficacy of empirical regimens for H. pylori eradication might decline with bacterial, drug, and host factors. The necessity of a tailored therapy still remains controversial. Here we provide a meta-analysis of the current status of susceptibility-based (tailored) therapy in which susceptibility-based therapies were compared to the currently accepted choice of empiric therapy. In this rapidly closing era, neither the susceptibility nor empiric therapies were routinely optimized, such that we report the outcome of comparisons on the efficacy of unoptimized tailored vs. locally preferred empiric treatments.

METHODS

PubMed, Medline, and Embase databases were searched using suitable keywords. Individual and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using the fixed- or random-effects model as appropriate. Heterogeneity was calculated employing the Cochrane Q test and I² values, whereas the possibility of publication bias was examined by constructing funnel plots. Additionally, subgroup and sensitivity analyses were performed.

RESULTS

Thirty-four studies were included with a total of 9613 patients. Tailored therapy proved superior to empiric treatment [OR 2.07 (95% CI 1.53-2.79)]. However, tailored therapy achieved eradication rates >90% in only 15 (44%) studies and >95% in only 6 (17.6%).

CONCLUSIONS

Although tailored therapy performed better than empiric treatment, the lack of optimization of therapies failed to reliably achieve high cure rates (>90%). These results emphasize that H. pylori infection, like other infectious diseases, should utilize the principles of antimicrobial stewardship in relation to treatment guidance.

Evaluation of guidelines for diagnosis and treatment of Helicobacter pylori infection

BACKGROUND

To systematically evaluate the quality of the guidelines for the diagnosis and treatment of Helicobacter pylori infection and to analyze the differences and reasons for the key recommendations in the guidelines.

METHODS

Databases and websites were systematically searched to obtain guidelines for the diagnosis and treatment of Helicobacter pylori infection. Four independent reviewers used the Guideline Evaluation Tool (AGREE II) to evaluate the included guidelines. The intraclass correlation coefficient (ICC) and Fleiss' kappa coefficient were used to measure the consistency of evaluation guidelines between guide reviewers. Differences between guidelines and the reasons for the differences were analyzed by comparing the recommendations of different guidelines and the evidence supporting the recommendations.

RESULTS

A total of 17 guidelines for Helicobacter pylori infection were included in this study. The AGREE II scores of these guidelines were low overall, with 4 of them had a score of over 60%, which indicates that the guidelines are recommended, and 13 of them having a score ranging from 30 to 60%, which indicates that the guidelines are recommended but need to be revised, while no guideline had a score of 30% or less, which indicates that they were not recommended. The analysis of these guidelines found that there were some differences in the main recommendations. Not all guidelines recommend sequential therapy as the recommended therapy. Whether bismuth quadruple therapy should be used as the recommended first-line therapy is unclear. The antibiotic resistance rate is different in different regions. Combined with the local antibiotic sensitivity test, the eradication rate of Helicobacter pylori can be improved.

CONCLUSION

There are significant differences in the quality of Helicobacter pylori infection guidelines and the key recommendations. Improving the deficiencies of existing guidelines is an effective way to develop high-quality guidelines and make reasonable recommendations for the treatment of Helicobacter pylori infection in the future.

How widespread and convenient H. pylori susceptibility testing will result in pharmacological opportunities

INTRODUCTION

Until recently, antimicrobial therapy for Helicobacter pylori infections was almost universally empirical and based on a combination of expert opinion and local effectiveness. However, the new requirement that all therapeutic regimens reliably achieve high cure rates, the introduction of potassium competitive acid blockers and the availability of susceptibility testing many pharmacological opportunities particularly since all current therapies will require optimization. The ability to rapidly and inexpensively obtain H. pylori susceptibility data using stool samples makes obtaining susceptibility data practical and allows using susceptibility-based therapy routinely for both treatment-naïve patient and treatment failures.

AREAS COVERED

We searched the literature from 1990 to current to identify studies reporting the effect of susceptibility testing on H. pylori treatment. This review examines how widespread and convenient H. pylori susceptibility testing will result in pharmacological opportunities. . Many pharmacological opportunities will emanate from a renewal of efforts to develop, propagate, confirm, and update best practices based on local and regional susceptibility/resistance patterns.

EXPERT OPINION

The ability to evaluate treatment decisions and outcomes in susceptible infections and reliably achieve high cure rates should foster precise tailoring of pharmacologic therapy and should achieve the goals of high cure rates while preventing antimicrobial misuse and extending the useful life of current antibiotics.

Personalized Approach in Eradication of Helicobacter pylori Infection

The increase in antibiotic resistance to Helicobacter pylori (H. pylori) is associated with a decrease in the effectiveness of eradication therapy. Although some success has been achieved by adjusting therapeutic regimens according to local data on resistance to certain antibiotics, a new approach is needed to ensure a better therapeutic response. Tailored therapy, based on sensitivity tests to antibiotics, is increasingly proving to be a superior therapeutic option, even as a first-line therapy. Moreover, the recently published Maastricht VI guidelines emphasize utilizing a susceptibility-guided strategy in respect to antibiotic stewardship as the first choice for eradication therapy. In addition, polymerase chain reaction (PCR) technology is becoming a standard tool in the diagnosis of H. pylori infections through non-invasive testing, which further optimizes the eradication process. We provide a review regarding the current position of the individualized approach in eradication therapy and its future prospects. Based on novel understandings, the personalized approach is an effective strategy to increase the successful eradication of H. pylori infections.

2022 Chinese national clinical practice guideline on Helicobacter pylori eradication treatment

BACKGROUND

Helicobacter pylori ( H. pylori ) infection is an infectious disease with a prevalence rate of up to 50% worldwide. It can cause indigestion, gastritis, peptic ulcer, and gastric cancer. H. pylori eradication treatment can effectively control disease progression and reduce the risk of the above conditions. However, the escalating trend of antibiotic resistance presents a global challenge for H. pylori eradication. We aim to provide guidance on pharmacological treatment of H. pylori infection.

METHODS

This clinical practice guideline is developed following the World Health Organization's recommended process, adopting Grading of Recommendations Assessment, Development and Evaluation in assessing evidence quality, and utilizing Evidence to Decision framework to formulate clinical recommendations, minimizing bias and increasing transparency of the clinical practice guideline development process. We used the Reporting Items for practice Guidelines in HealThcare (RIGHT) statement and The Appraisal of Guidelines for Research and Evaluation II (AGREE II) as reporting and conduct guides to ensure the guideline's completeness and transparency.

RESULTS

Though decreasing in developed countries, the prevalence of H. pylori remains high in developing countries, causing a major public health burden. This clinical practice guideline contains 12 recommendations concerning pharmacological treatment for H. pylori eradication. Among them, it is worth highlighting that bismuth preparations are inexpensive, safe, and effective, consequently making bismuth quadruple therapy a preferred choice for initial and rescue treatment. In empirical treatment, high-dose dual therapy is equally effective compared with bismuth quadruple therapy.

CONCLUSIONS

The 12 recommendations in this clinical practice guideline are formed with consideration for stakeholders' values and preferences, resource use, feasibility, and acceptability. Recommendations are generalizable to resource limited settings with similar antibiotic resistance pattern as China, and lower middle-income countries facing comparable sociological and technical challenges.

REGISTRATION

Guidelines International Network (GIN) website, https://guidelines.ebmportal.com/node/69996 .

The cure rate of 10-day bismuth-containing quadruple therapy for Helicobacter pylori eradication is equivalent to 14-day: a systematic review and meta-analysis

Helicobacter pylori (H. pylori) infection is a major cause of duodenal ulcers, gastric ulcers, and gastric cancer. However, the optimal duration for H. pylori eradication therapy remains controversial. Most studies have mainly focused on triple therapy, and there is insufficient research on bismuth-containing quadruple therapy. The aim of this study was to compare the clinical effect of the 10-day bismuth-containing quadruple treatment regimen with the 14-day regime in eradicating H. pylori. We searched PubMed, Embase, Web of Science, and the Cochrane Library for randomized controlled trials published in English until May 2022 according to the eligibility criteria. Summary risk ratios (RRs) and 95% confidence intervals (CIs) for eradication rates, adverse effects, and compliance were calculated for included studies. Four studies, involving 1173 patients, were eligible for inclusion. The eradication rate was similar in the 10-day treatment group and the 14-day treatment group in the intention-to-treat analysis (RR 0.97, 95% CI 0.93 to 1.01). Meanwhile, the incidence of adverse effects was lower in patients who received 10 days of treatment than in those who received 14 days of treatment and patients' compliance was almost the same between two groups. Compared to the 14-day bismuth-containing quadruple regimens, 10-day regimens had similar efficacy and lower incidence of adverse effects. Therefore, the 10-day regimen is safe and well-tolerated and should be recommended for H. pylori infection.

Evaluation of a Molecular Mosprie Assay for Detection of Helicobacter pylori and Resistance to Clarithromycin and Levofloxacin

BACKGROUND

Helicobacter pylori eradication regimens should be guided by antimicrobial susceptibility testing. The objective of this study was to evaluate the molecular-based Mosprie assay for detecting H. pylori resistance to clarithromycin and levofloxacin using gastric biopsies.

METHODS

A total of 185 culture-positive frozen gastric biopsies were included for Mosprie assay and also for 23S rRNA and gyrA gene sequencing. The susceptibility results by the Mosprie assay were compared with the E-test results retrospectively retrieved. The discordant results were analyzed by sequencing of the 23S rRNA and gyrA genes.

RESULTS

Susceptibility concordance between the Mosprie assay and E-test for clarithromycin and levofloxacin was 97.30% (180/185) and 88.11% (163/185), respectively. The full agreement between clarithromycin genotypes by Mosprie assay and the 23S rRNA sequencing results was observed in the 5 samples with discordant Mosprie assay and E-test results. However, for levofloxacin, of the 16 discordant samples with resistant phenotype but a susceptible genotype by Mosprie assay, 6 were found to have levofloxacin resistance-related gyrA gene mutations.

CONCLUSIONS

The rapid and reliable Mosprie assay can be recommended for H. pylori susceptibility testing of clarithromycin and levofloxacin on gastric biopsies. Future technical improvements are needed in detecting levofloxacin resistance-associated gene mutations.

Reassessment of the Broth Microdilution Method for Susceptibility Testing of Helicobacter pylori

BACKGROUND

Helicobacter pylori infection is an infectious disease and thus the eradication treatment should be guided by susceptibility testing. This study aimed to assess the applicability of broth microdilution as a routine susceptibility testing method for H. pylori.

METHODS

Susceptibility profiles of clarithromycin (CLR) and levofloxacin (LEV) resistance in 76 clinical H. pylori isolates were simultaneously assessed using agar dilution and broth microdilution methods. The correlation between the minimum inhibitory concentrations (MICs) obtained by the 2 methods was assessed by means of linear regression analysis.

RESULTS

The correlation between the MICs determined by broth microdilution method and agar dilution method was good for both CLR (r = 0.966) and LEV (r = 0.959). The susceptibility agreement between the 2 methods was 100% for CLR and 96.1% for LEV. Using the broth microdilution method, the false resistance was found in 3.9% (3 of 76) strains for LEV susceptibility testing. No false susceptibility was found for either CLR or LEV, and no false resistance was found for susceptibility testing of CLR.

CONCLUSIONS

The broth microdilution method is suitable for routine susceptibility testing of clinical H. pylori isolates.

Multiple Bismuth Quadruple Therapy Containing Tetracyclines Combined with Other Antibiotics and Helicobacter pylori Eradication Therapy

Helicobacter pylori (HP) infection is closely associated with the development of chronic gastritis, peptic ulcer, and gastric cancer. However, the resistance rate of H. pylori strains to antibiotics such as clarithromycin, metronidazole, and levofloxacin has increased significantly, resulting in a significant decrease in the eradication efficacy of commonly used regimens. Tetracycline has received the attention of domestic and foreign scholars because of its low resistance. The purpose of this review is to provide an update on the tetracycline-containing bismuth quadruple eradication therapy for H. pylori infection and review the efficacy and safety of the regimens, hoping to provide guidance for clinical practice.

Short-term outcomes and intermediate-term follow-up of Helicobacter pylori infection treatment for naïve patients: a retrospective observational study

OBJECTIVES

To explore the outcomes of Helicobacter pylori infection treatments for naïve patients in the real-world settings.

DESIGN

A retrospective observational study.

SETTING

Single tertiary level academic hospital in China.

PARTICIPANTS

We identified patients initially receiving quadruple therapy for H. pylori infection from 2017 to 2020 in whom eradication was confirmed (n=23 470).

PRIMARY OUTCOME

Efficacy of different initial H. pylori infection treatments.

SECONDARY OUTCOME

Results of urea breath test (UBT) after H. pylori eradication.

RESULTS

Among 23 470 patients who received initial H. pylori treatment, 21 285 (90.7%) were treated with amoxicillin-based regimens. The median age of the patients decreased from 2017 to 2020 (45.0 vs 39.0, p<0.0001). The main treatments were therapies containing amoxicillin and furazolidone, which had an eradication rate of 87.6% (14 707/16 784); those containing amoxicillin and clarithromycin had an eradication rate of 85.5% (3577/4182). The date of treatment, age, antibiotic regimen and duration of treatment showed correlations with the failure of H. pylori eradication in a multivariable logistic regression analysis. Finally, positive UBT results after eradication clustered around the cut-off value, in both the ¹³C-UBT and ¹⁴C-UBT.

CONCLUSIONS

The major H. pylori infection treatments for naïve patients were those containing amoxicillin and furazolidone, which offered the highest eradication rate. The date of treatment, age, antibiotic regimen and duration of treatment were risk factors for the failure of H. pylori eradication. Additionally, positive UBT results after eradication clustered around the cut-off value.

Tailored therapy for Helicobacter pylori eradication: A systematic review and meta-analysis

Background: Due to an increase in drug resistance, the eradication rate of H. pylori with empirical therapy has declined. Tailored therapy has been proposed as an alternative to standard empirical treatments. The necessity of personalized eradication therapy remains unclear. The aim of this study was to determine whether tailored therapy is superior to empirical therapy for H. pylori infection.

Methods: We searched for eligible randomized controlled trials in the PubMed, Embase (Ovid), Wanfang, and Cochrane Central Register of Controlled Trials databases up to 10 December 2021. A random effects model comparing pooled relative risks (RRs) with 95% confidence intervals (CIs) was applied in the meta-analysis.

Results: Twenty-one studies were included in the meta-analysis. In the first-line treatment, tailored therapy was more effective than empirical therapy (RR, 1.14 [95% CI, 1.08–1.21], I² = 72.2%). In the second-line therapy setting, the results did not reveal significant differences between the two treatments (RR, 1.05 [95% CI, 0.84–1.30], I² = 80.6%). A similar result was observed in mixed second- and third-line treatments (RR, 1.03 [95% CI, 0.96–1.11], I² = 0.0%). Regarding adverse events, no significant differences were found between the two treatments (RR, 0.90 [95% CI, 0.80–1.01], I² = 35.7%). Most of the results were highly heterogeneous.

Conclusion: A tailored approach might provide a better eradication rate than empirical methods in first-line treatment. There might be no obvious advantage in second-line or mixed second- and third-line treatments third-line treatment. Due to the high heterogeneity, the results should be interpreted with caution. Further clinical studies are needed and justified.

Susceptibility-guided vs. empirical 10-day quadruple treatment for Helicobacter pylori-infected patients: A prospective clinical trial of first-line therapy

Background

The increasing antimicrobial resistance of Helicobacter pylori (H. pylori) has resulted in a fall in cure rates. We aimed to assess the effectiveness of first-line susceptibility-guided therapy and furazolidone-based quadruple therapy for H. pylori-infected patients.

Methods

Subjects with H. pylori-infection were randomly assigned to either 10-day susceptibility-guided treatment or empiric treatment in a 2:1 ratio. Susceptibility-guided therapy was based on susceptibility to clarithromycin, and patients with susceptible strains received clarithromycin 500 mg twice daily and otherwise minocycline 100 mg twice a day was administered. Patients in the empiric therapy group was treated with furazolidone 100 mg twice a day. During treatment, all patients were given esomeprazole 20 mg twice daily, colloidal bismuth pectin 200 mg twice daily, and amoxicillin 1 g twice daily.

Results

A total of 248 patients were screened and 201 were finally included. Empiric and susceptibility-guided regimens were both successful with per-protocol eradication rates of 90.5% (57/63) vs. 88.5% (108/122) (p = 0.685) and intent-to-treat eradication rates of 85.1% (57/67) vs. 80.6% (108/134) (p = 0.435). No significant difference in eradication rates were observed among the furazolidone group, clarithromycin group and minocycline group.

Conclusion

Both susceptibility-guided therapy and quadruple therapy containing furazolidone can achieve good eradication rates. For population with a high rate of resistance, quadruple therapy containing furazolidone and bismuth may be a more practical choice for first-line treatment.

The changing profile of Helicobacter pylori primary antibiotic resistance in Singapore over two decades

Objectives

Antibiotic resistance is a key reason for Helicobacter pylori (H. pylori) treatment failure and updated local data are important to guide the choice of empiric first‐line therapy. Clarithromycin‐based triple therapy (TT) is currently the first‐line treatment in Singapore. Our primary aim was to determine the change in pattern of primary antibiotic resistance of H. pylori in Singapore as well as TT success rate.

Methods

A registry of H. pylori isolates was tested for primary antibiotic resistance and were analyzed from year 2001 to 2020. Treatment outcome data based on 13C‐urea breath test (13C‐UBT) results of empiric first‐line 2‐week TT from 2019 to 2020 were also analyzed retrospectively.

Results

A total of 387 H. pylori isolates were included. Rates of resistance to clarithromycin as well as tetracycline showed a downtrend in the last 5 years (clarithromycin: 2001–2002: 8.57%; 2007–2008: 14.14%; 2013–2014: 18.09%; 2019–2020: 13.71%; tetracycline: 2001–2002: 5.71%; 2007–2008: 7.07%; 2013–2014: 7.45%; 2019–2020: 0%). The resistance rate for amoxicillin remained low (2001–2002: 2.86%; 2007–2008: 5.05%; 2013–2014: 4.26%; 2019–2020: 7.26%). There was a steady increase in the rate of levofloxacin resistance (2001–2002: 5.71%; 2007–2008: 11.11%; 2013–2014: 15.96%; 2019–2020: 16.94%). From 2019 to 2020, the rate of successful TT was 91.67% (891/972).

Conclusion

The latest rate of clarithromycin resistance in 2019 to 2020 remained below the threshold of 15% and eradication rates remain high; thus, TT remains appropriate as an empiric first‐line treatment in Singapore.

Primary Antibiotic Resistance of Helicobacter pylori in Different Regions of China: A Systematic Review and Meta-Analysis

Aim: Understanding the prevalence of antibiotic resistance can provide reliable information for selecting treatment options. The goal of this meta-analysis was to observe the primary antibiotic resistance of Helicobacter pylori (H. pylori) in different regions and time periods of China. Method: We searched PubMed, EMBASE, Chinese Biomedical databases and the China National Knowledge Infrastructure from inception to 20 February 2022. Data on the prevalence of H. pylori primary resistance at various time points were included. A random-effect model was established to calculate the pooled antibiotic resistance. Results: In total, 2150 articles were searched, with 70 meeting the inclusion criteria. The resistance to clarithromycin, metronidazole, levofloxacin amoxicillin, tetracycline and furazolidone in 2016–2020 were 34% (95% CI: 30–39%), 78% (95% CI: 73–84%), 35% (95% CI: 30–40%), 3% (95% CI: 1–5%), 2% (95%CI: 1–4%) and 1% (95% CI: 0–4%), respectively. Clarithromycin showed regional difference, as the resistance was higher in northern (37%, 95% CI: 32–41%) and western China (35%, 95% CI: 17–54%) than that in southern (24%, 95% CI: 17–32%) and eastern China (24%, 95% CI: 20–28%). Conclusion: The resistance of H. pylori to clarithromycin and metronidazole was high and increased over time, whereas resistance to levofloxacin, amoxicillin, tetracycline and furazolidone remained stable.

Susceptibility testing alone will not reliably achieve high Helicobacter pylori cure rates: A systematic review and meta-analysis

BACKGROUND AND AIM

Not all the susceptibility-guided therapies for Helicobacter pylori (H. pylori) infection achieve excellent eradication rates. The aim of this study was to perform a systematic review and meta-analysis to identify the optimal regimen for H. pylori treatment based on antibiotic susceptibility.

METHODS

A systematic search was performed in multiple databases. Studies reporting eradication rates of H. pylori with susceptibility-guided therapies were selected. Meta-analysis was conducted to calculate the pooled eradication rate among the treatment regimens.

RESULTS

Forty-eight eligible studies with 101 susceptibility-guided treatment arms were included. The overall eradication rate in patients harboring susceptible strains was 95.0% (95% CI, 94.1-95.9%), but only 63.4% of treatment arms (64/101) achieved good eradication rates (≥ 90%). Pooled eradication rates in patients with susceptible strains were: 93.4% (95% CI, 92.0-94.8%) for clarithromycin, 99.0% (95% CI, 98.1-100%) for nitroimidazoles and 95.4% (95% CI, 93.6-97.2%) for fluoroquinolones. Among the arms using a triple therapy, 66.7% (28/42) using clarithromycin, 84.2% (16/19) using nitroimidazoles and 70.8% (17/24) using fluoroquinolones achieved good (≥ 90%) eradication rates. Of 13 arms using sequential therapy, ≥ 90% eradication was achieved in 14.3% (1/7) using clarithromycin, 25.0% (1/4) using nitroimidazoles and both arms (2/2) using fluoroquinolones.

CONCLUSIONS

Susceptibility testing alone seemed insufficient to reliably attain high H. pylori cure rates. The eradication rate in patients with nitroimidazoles susceptible strains was higher than those of fluoroquinolones and clarithromycin.

Empirical vs. Susceptibility-Guided Treatment of Helicobacter pylori Infection: A Systematic Review and Meta-Analysis

Background

Treating Helicobacter pylori infection according to antibiotic resistance has been frequently recommended. However, information on its real effectiveness is scarce.

Aim

The aim of this study is to perform a meta-analysis comparing empirical vs. susceptibility-guided treatment of H. pylori.

Methods

Selection of studies: Studies comparing empirical versus susceptibility-guided treatment were selected. Search strategy: electronic and manual up to August 2021. Data synthesis: by intention-to-treat (random-effects model).

Results

Overall, 54 studies were included (6,705 patients in the susceptibility-guided group and 7,895 in the empirical group). H. pylori eradication rate was 86 vs. 76%, respectively (RR: 1.12; 95% CI: 1.08-1.17; I 2: 83%). Similar results were found when only RCTs were evaluated (24 studies; RR: 1.16; 95% CI: 1.11-1.22; I 2: 71%) and when susceptibility testing was assessed by culture (RR: 1.12; 95% CI: 1.06-1.18) or PCR (RR: 1.14; 95% CI: 1.05-1.23). For first-line treatments (naïve patients; 30 studies), better efficacy results were obtained with the susceptibility-guided strategy (RR: 1.15; 95% CI: 1.11-1.20; I 2: 79%). However, for empirical first-line quadruple regimens, in particular (both with and without bismuth, excluding the suboptimal triple therapies), not based on CYP2C19 gene polymorphism, no differences in efficacy were found compared with the susceptibility-guided group (RR: 1.04; 95% CI: 0.99-1.09); this lack of difference was confirmed in RCTs (RR: 1.05; 95% CI: 0.99-1.12). For rescue therapies (13 studies, most 2nd-line), similar results were demonstrated for both strategies, including all studies (RR: 1.09; 95% CI: 0.97-1.22; I 2: 82%) and when only RCTs were considered (RR: 1.15; 95% CI: 0.97-1.36).

Conclusion

The benefit of susceptibility-guided treatment over empirical treatment of H. pylori infection could not be demonstrated, either in first-line (if the most updated quadruple regimens are prescribed) or in rescue therapies.

Primer for Development of Guidelines for Helicobacter pylori Therapy Using Antimicrobial Stewardship

We provide a primer to assist in the difficult transition of Helicobacter pylori therapy guidelines to those that adhere to the principles of antimicrobial stewardship. This transition will entail abandonment of many of the principles that heretofore formed the basis of treatment guidelines and recommendations. The goals of antimicrobial stewardship include optimization of the use of antibiotics while reducing antimicrobial resistance. The critical outcome measure is absolute cure rate which largely restricts comparative trials to those which reliably produce high cure rates (eg, ∼95%). Therapies that fail to achieve at least a 90% cure rate should be abandoned as unacceptable. Because only optimized therapies should be prescribed, guidance on the principles and practices of optimization will we required. Therapies that contain antibiotics which do not contribute to outcome should be eliminated. Surveillance, one of the fundamental elements of antimicrobial stewardship, must be done to provide ongoing assurance that the recommended therapies remain effective. It is yet not widely recognized when utilizing otherwise highly successful therapies, the routine test of cure data is an indirect, surrogate method for susceptibility testing. To systematically guide therapy, test of cure data should be collected, shared and integrated into local antimicrobial stewardship programs to provide guidance regarding best practices to both prescribers and public health individuals. Treatment recommendations should be compatible with those of the American Society of Infectious Disease white paper on the conduct of superiority and organism-specific clinical trials of antibacterial agents for the treatment of infections caused by drug-resistant bacterial pathogens which include criteria for ethical active-controlled superiority studies of antibacterial agents.

The Influence of Past Metronidazole Exposure on the Outcome of Helicobacter pylori Eradication

Background

Bismuth quadruple therapy (BQT) is recommended as empirical first-line therapy because it is not affected by antibiotic resistance. We examined whether past exposure to metronidazole affected BQT outcomes.

Methods

The records of seven hospitals were searched for patients who received BQT for Helicobacter pylori eradication between 2009 and 2020. The association between past metronidazole exposure and the eradication rate was evaluated.

Results

This study was a multicenter retrospective study. Around 37,602 people tested for H. pylori infection were identified, and 7,233 received BQT. About 2,802 (38.7%) underwent a 13C-urea breath test to confirm eradication. The BQT efficacy was 86.4% among patients without metronidazole exposure and 72.8% among patients with exposure (p < 0.001). The eradication rate of BQT 14 days in patients with past exposure was higher than that of BQT <14 days (85.5 vs. 66.0%, p = 0.009). Multivariate analysis revealed that past metronidazole exposure [odds ratio (OR) 2.6, 95% CI 1.8–3.7; p < 0.001] and BQT <14 days (OR 1.5, 95% CI 1.2–2.0; p = 0.002) were independent risk factors for eradication failure.

Conclusion

Past metronidazole exposure significantly lowered the BQT eradication rate. BQT 14 days should be recommended for patients with suspected metronidazole exposure.

E-Test or Agar Dilution for Metronidazole Susceptibility Testing of Helicobacter pylori: Importance of the Prevalence of Metronidazole Resistance

Background

A number of studies have shown that E-test overestimated the presence of Helicobacter pylori resistance compared to agar dilution.

Objective

The purpose of this study was to explore whether E-test could be an alternative for agar dilution to detect the metronidazole susceptibility of H. pylori.

Method

E-test and agar dilution were used to assess the susceptibility of H. pylori to metronidazole, clarithromycin, and levofloxacin in 281 clinical isolates obtained from China where the resistance was high. Cohen’s kappa analysis, McNemar’s test, and essential and categorical agreement analysis were performed for these two methods.

Results

Overall, the result of the E-test showed a similar prevalence of resistance rate to all antibiotics compared with agar dilution. The essential agreement of the E-test method and agar dilution in the evaluation susceptibility of H. pylori to clarithromycin and levofloxacin was moderate at 89.0 and 79.7%, respectively, but only 45.9% for metronidazole. The results shown by a categorical agreement (CA) between the E-test and agar dilution were 100% for both clarithromycin and levofloxacin. As for metronidazole, the CA was 98.7%, no major error was identified, and the rate of a very major error was 1.8%.

Conclusion

E-test can be an alternative method to detect the metronidazole susceptibility of H. pylori.

Need for standardization and harmonization of Helicobacter pylori antimicrobial susceptibility testing

BACKGROUND AND AIMS

As with other infectious diseases, Helicobacter pylori eradication regimens should be guided by susceptibility testing to achieve excellent success rate, especially in the era of high antibiotic resistance. However, susceptibility testing for H. pylori is rarely performed, which can be partly ascribed to the current lack of standardization of testing methods and the lack of unified consensus on the antibiotic resistance breakpoints. The aim of this review was to call for an international consensus on standardization and harmonization of H. pylori susceptibility testing.

METHODS

We summarize and compare the advantages and disadvantages of four different phenotypic antimicrobial susceptibility testing (AST) methods (agar dilution, E-test, disk diffusion, and broth microdilution) and the molecular susceptibility testing method for H. pylori.

RESULTS

The standard phenotypic testing methods and the molecular testing methods have their own advantages and disadvantages. Compared to the standard phenotypic methods, the molecular testing method does not require successful H. pylori culture, and therefore, is much more rapid and convenient for clinical use. However, the currently available molecular testing method is only suitable for detecting clarithromycin and quinolone susceptibility profiles in H. pylori. Although the standard AST is time-consuming, it is currently the only way to test the susceptibility of H. pylori to all the commonly used antibiotics.

CONCLUSION

To make H. pylori susceptibility testing become a clinical routine, an international consensus on standardization and harmonization of H. pylori AST is needed. Future efforts are needed for optimizing broth culture of H. pylori, and developing commercial AST plates for achieving high throughput and automated susceptibility testing for H. pylori.

Susceptibility-Guided Therapy vs. Bismuth-Containing Quadruple Therapy as the First-Line Treatment for Helicobacter pylori Infection: A Systematic Review and Meta-Analysis

Background

The increased antibiotic resistance of Helicobacter pylori (H. pylori) has led to the decreased efficacy of H. pylori regimens.

Aim

To evaluate the efficacy, safety, and compliance of susceptibility-guided therapy (SGT) vs. bismuth-containing quadruple therapy (BQT) as the first-line treatment for H. pylori infection.

Materials and Methods

This meta-analysis was performed in accordance with the PRISMA 2009 guidelines. A systematic search in PubMed, Embase, and Cochrane databases was conducted using the combination of “H. pylori or H. pylori or Hp,” “bismuth quadruple,” and “tailored eradication OR tailored therapy OR susceptibility-guided therapy OR personalized therapy OR antibiotic susceptibility testing.”

Results

Five studies with 2,110 H. pylori-infected patients were enrolled. The pooled eradication rates of SGT and BQT were 86 vs. 78% (p < 0.05) and 92 vs. 86% (p > 0.05) by intention-to-treat (ITT) and per-protocol (PP) analyses, respectively. SGT has a significantly superior efficacy than BQT [pooled risk ratio (RR) = 1.14, p < 0.05] in a subgroup of cultures with the susceptibility test. The pooled side effect rate was 20% in SGT and 22% in BQT, which showed no significant difference (p > 0.05). The compliances of SGT and BQT were 95 and 92%, respectively.

Conclusion

Compared with BQT, SGT showed a higher efficacy and similar safety as the first-line treatment of H. pylori infection in areas with high antibiotic resistance. The decision-making of first-line regimens for H. pylori infection should depend on the availability and cost-effectiveness of susceptibility tests and bismuth in local areas.

Chinese Consensus Report on Family-Based Helicobacter pylori Infection Control and Management (2021 Edition)

OBJECTIVE

Helicobacter pylori infection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for population-wide and family-based H. pylori infection control and management to reduce the related disease burden.

METHODS

Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements.

RESULTS

Experts discussed and modified the original 23 statements on family-based H. pylori infection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1) H. pylori infection and transmission among family members, (2) prevention and management of H. pylori infection in children and elderly people within households, and (3) strategies for prevention and management of H. pylori infection for family members. In addition to the 'test-and-treat' and 'screen-and-treat' strategies, this consensus also introduced a novel third 'family-based H. pylori infection control and management' strategy to prevent its intrafamilial transmission and development of related diseases.

CONCLUSION

H. pylori is transmissible from person to person, and among family members. A family-based H. pylori prevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas.

Assessment of first-line eradication treatment in Greece: data from the European Registry on Helicobacter pylori management (Hp-EuReg)

Background

Helicobacter pylori (H. pylori) is the most common chronic bacterial infection. Its management has to rely on local effectiveness, given the geographical variability of bacterial antibiotic resistance. We evaluated treatment effectiveness in naïve patients in Greece, as part of the European Registry on the management of H. pylori (Hp-EuReg).

Methods

Patients were registered in the AEG-REDCap Electronic Case Report Form from 2013-2020. All cases with a first-line treatment were included. Modified intention-to-treat (mITT) analysis was used.

Results

A total of 547 patients from 5 medical institutions were treated with the following regimens: concomitant with proton pump inhibitors (PPIs), clarithromycin, amoxicillin and metronidazole (concomitant-C+A+M) (38%); hybrid with PPI, clarithromycin, amoxicillin and metronidazole (hybrid-C+A+M) (20%); sequential with PPI, clarithromycin, amoxicillin and tinidazole (sequential-C+A+T) (12%); sequential with PPI, clarithromycin, amoxicillin and metronidazole (sequential-C+A+M) (12%); concomitant with PPI, clarithromycin, amoxicillin and tinidazole (concomitant-C+A+T) (8%); triple with PPI, clarithromycin and amoxicillin (triple-C+A) (7%); and other (3%). Overall compliance was 99%. Triple-C+A, sequential-C+A+T, sequential-C+A+M and concomitant-C+A+T were used from 2013-2015. The respective mITT cure rates (95% confidence interval) were 92% (78-98), 87% (76-94), 67% (54-78) and 91% (79-98). Since 2015, patients were also treated with concomitant-C+A+M and hybrid-C+A+M regimens, with respective mITT cure rates of 90% (85-94) and 88% (80.5-94). Adverse events were reported by 31% of the patients, dysgeusia being the most frequent (15%).

Conclusions

“Optimized” H. pylori therapies should achieve cure rates over 90%. In Greece, at present, only non-bismuth quadruple concomitant regimens achieve this target and can be recommended as first-line treatment.

Helicobacter pylori diagnosis and therapy in the era of antimicrobial stewardship

The diagnosis and therapy of Helicobacter pylori infection have undergone major changes based on the use the principles of antimicrobial stewardship and increased availability of susceptibility profiling. H. pylori gastritis now recognized as an infectious disease, as such there is no placebo response allowing outcome to be assessed in relation to the theoretically obtainable cure rate of 100%. The recent recognition of H. pylori as an infectious disease has changed the focus to therapies optimized to reliably achieve high cure rates. Increasing antimicrobial resistance has also led to restriction of clarithromycin, levofloxacin, or metronidazole to susceptibility-based therapies. Covid-19 resulted in the almost universal availability of polymerase chain reaction testing in hospitals which can be repurposed to utilize readily available kits to provide rapid and inexpensive detection of clarithromycin resistance. In the United States, major diagnostic laboratories now offer H. pylori culture and susceptibility testing and American Molecular Laboratories offers next-generation sequencing susceptibility profiling of gastric biopsies or stools for the six commonly used antibiotics without need for endoscopy. Current treatment recommendations include (a) only use therapies that are reliably highly effective locally, (b) always perform a test-of-cure, and (c) use that data to confirm local effectiveness and share the results to inform the community regarding which therapies are effective and which are not. Empiric therapy should be restricted to those proven highly effective locally. The most common choices are 14-day bismuth quadruple therapy and rifabutin triple therapy. Prior guidelines and treatment recommendations should only be used if proven locally highly effective.

Comparison of Culture With Antibiogram to Next-Generation Sequencing Using Bacterial Isolates and Formalin-Fixed, Paraffin-Embedded Gastric Biopsies

BACKGROUND & AIMS

The decline in Helicobacter pylori cure rates emphasizes the need for readily available methods to determine antimicrobial susceptibility. Our aim was to compare targeted next-generation sequencing (NGS) and culture-based H pylori susceptibility testing using clinical isolates and paired formalin-fixed, paraffin-embedded (FFPE) gastric biopsies.

METHODS

H pylori isolates and FFPE tissues were tested for susceptibility to amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and rifabutin using agar dilution and NGS targeted to 23S rRNA, gyrA, 16S rRNA, pbp1, rpoB and rdxA. Agreement was quantified using κ statistics.

RESULTS

Paired comparisons included 170 isolates and FFPE tissue for amoxicillin, clarithromycin, metronidazole, and rifabutin and 57 isolates and FFPE tissue for levofloxacin and tetracycline. Agreement between agar dilution and NGS from culture isolates was very good for clarithromycin (κ = 0.90012), good for levofloxacin (κ = 0.78161) and fair for metronidazole (κ = 0.55880), and amoxicillin (κ = 0.21400). Only 1 isolate was resistant to tetracycline (culture) and 1 to rifabutin (NGS). Comparison of NGS from tissue blocks and agar dilution from isolates from the same stomachs demonstrated good accuracy to predict resistance for clarithromycin (94.1%), amoxicillin (95.9%), metronidazole (77%), levofloxacin (87.7%), and tetracycline (98.2%). Lack of resistance precluded comparisons for tetracycline and rifabutin.

CONCLUSIONS

Compared with agar dilution, NGS reliably determined resistance to clarithromycin, levofloxacin, rifabutin, and tetracycline from clinical isolates and formalin-fixed gastric tissue. Consistency was fair for metronidazole and amoxicillin. Culture-based testing can predict treatment outcomes with clarithromycin and levofloxacin. Studies are needed to compare the relative ability of both methods to predict treatment outcomes for other antibiotics.

Susceptibility-guided versus empirical treatment for Helicobacter pylori infection: A systematic review and meta-analysis

BACKGROUND AND AIM

Empirical therapy for Helicobacter pylori infection is limited by increasing antibiotic resistance and suboptimal eradication rates. Studies of the relative effectiveness of susceptibility-guided therapy have produced conflicting results. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to determine whether susceptibility-guided therapy is superior to empirical therapy for H. pylori infection.

METHODS

We searched articles listed in PubMed, MEDLINE, EMBASE, and Web of Science through May 25, 2020, RCTs comparing susceptibility-guided versus empirical therapy for H. pylori infection. Outcomes, including effectiveness and safety, were analyzed in a meta-analysis.

RESULTS

Our final analysis included 16 studies, comprising 2374 patients who received susceptibility-guided therapy and 2451 patients who received empirical treatment. In previously untreated subjects, susceptibility-guided therapy was slightly more effective than empirical therapy (intent to treat risk ratio [RR], 1.14; 95% confidence interval [CI], 1.07-1.21; P < 0.0001, I²  = 75%). Susceptibility-guided therapy was superior to first-line clarithromycin-based triple therapy only when clarithromycin resistance exceeded 20% (RR, 1.18; 95% CI, 1.07-1.30; P = 0.001, I²  = 81%). Susceptibility-guided therapy was not more effective than empirical quadruple therapy (RR, 1.02; 95% CI, 0.92-1.13; P = 0.759, I²  = 80%). Three RCTs were performed exclusively among previously treated subjects, and were highly heterogeneous.

CONCLUSIONS

Our findings suggest that susceptibility-guided treatment may be slightly superior to empirical first line triple therapy. Susceptibility- guided treatment does not appear to be superior to empirical first-line quadruple therapy or empirical rescue therapy.

Modified quadruple therapy or bismuth-containing quadruple therapy in the first-line treatment of Helicobacter pylori in Turkey

AIM

Helicobacter pylori (H. pylori) eradication is still an important issue in countries with high antibiotic resistance. This study aimed to compare the efficacy and safety of two bismuth-containing treatment modalities in H. pylori treatment in Turkey.

MATERIAL AND METHODS

subjects with H. pylori infection who were treated with either bismuth-containing quadruple therapy (pantoprazole 40 mg bid, tetracycline 500 mg qid, metronidazole 500 mg tid, bismuth subcitrate 262 mg qid daily) (BQT group) or modified quadruple therapy (pantoprazole 40 mg bid, amoxicillin 1 g bid, metronidazole 500 mg tid, bismuth subcitrate 262 mg qid daily) (MBQT group) for 14 days were compared, retrospectively. The eradication success rate, adverse events related to the medications and compliance were investigated.

RESULTS

a total of 128 patients in the BQT group and 102 patients in the MBQT group completed the treatment. The overall rate of adverse events was significantly higher in the BQT group compared with the MBQT group (39.4 % vs 18.6; p: 0.001). Among the adverse events, nausea-vomiting and abdominal discomfort was significantly more frequent in the BQT group than in the MBQT group (p: 0.001). The adverse events were mild-moderate in both groups and life threatening adverse events were not present in any of the patients.

CONCLUSION

although both regimens were highly effective and safe in H. pylori eradication, both intention-to-treat (ITT) and per-protocol (PP) eradication rates were higher and adverse events were lower in the modified quadruple therapy group. Modified quadruple therapy should be kept in mind for the first-line treatment of H. pylori in regions with high clarithromycin and metronidazole resistance.

Comparative Effectiveness of Multiple Different First-Line Treatment Regimens for Helicobacter pylori Infection: A Network Meta-analysis

BACKGROUND & AIMS

A number of double, triple, and quadruple therapies have been proposed as first-line empiric treatments for Helicobacter pylori infection. However, knowledge of their worldwide and regional comparative efficacy is lacking. We examined the comparative effectiveness of all empirically used first-line regimens tested against standard triple treatment using a network meta-analysis of published randomized controlled trials.

METHODS

Data extracted from eligible randomized controlled trials were entered into a Bayesian network meta-analysis to investigate the comparative efficacy of H pylori infection empiric first-line regimens and to explore their effectiveness rank order. The ranking probability for each regimen was evaluated by means of surfaces under cumulative ranking values.

RESULTS

Sixty-eight eligible randomized controlled trials were included, giving a total of 92 paired comparisons with 22,975 patients randomized to 8 first-line regimens. The overall results showed that only vonoprazan triple therapy and reverse hybrid therapy achieved cure rates of >90%. Levofloxacin triple therapy performed best in Western countries (eradication rate 88.5%). The comparative effectiveness ranking showed that vonoprazan triple therapy had the best results, whereas standard triple therapy was the least efficacious regimen (surfaces under cumulative ranking 92.4% vs 4.7% respectively; odds ratio, 3.80; 95% credible interval, 1.62-8.94).

CONCLUSIONS

For first-line empiric treatment of H pylori infection, vonoprazan triple therapy and reverse hybrid therapy achieved high eradication rates of >90%. Levofloxacin triple therapy achieved the highest eradication rates in Western countries. Standard triple therapy was the least efficacious regimen in this network meta-analysis.

The status and progress of first-line treatment against Helicobacter pylori infection: a review

Helicobacter pylori (HP) is a major causative agent of chronic gastritis and peptic ulcer. HP is also engaged in the development of gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. It is an important pathogenic factor in various other systemic diseases, such as vitamin B12 deficiency, iron deficiency, and idiopathic thrombocytopenia. The current consensus is that unless there is a special reason, eradication therapy should be implemented whenever HP infection is found, and it is ideally successful the first time. International guidelines recommend that under certain conditions, treatment should be personalized based on drug susceptibility testing. However, drug susceptibility testing is often not available because it is expensive, time-consuming, and difficult to obtain living tissue. Each region has separately formulated guidelines or consensuses on empirical therapy. Owing to an increasing drug resistance rate in various places, the eradication rate of proton pump inhibitor (PPI) triple therapy and sequential therapy has been affected. These regimens are rarely used; the PPI triple especially has been abandoned in most areas. Currently, radical treatment regimens for HP involve bismuth-containing quadruple therapy and concomitant therapy. However, quadruple therapy has its own limitations, such as complex drug administration. To improve the effectiveness, safety, and compliance, many clinical studies have proposed useful modified regimens, which mainly include the modified bismuth-containing quadruple regimen, high-dose dual therapy, and vonoprazan-containing regimens. Studies have shown that these emerging regimens have acceptable eradication rates and safety, and are expected to become first-line treatments in empirical therapy. However, the problem of decline in the eradication rate caused by drug resistance has not been fundamentally solved. This review not only summarizes the effectiveness of mainstream regimens in the first-line treatment of HP infection with the currently increasing antibiotic resistance rates, but also summarizes the effectiveness and safety of various emerging treatment regimens.

Evaluation of safety and pharmacokinetics of bismuth-containing quadruple therapy with either vonoprazan or lansoprazole for Helicobacter pylori eradication

Aims

Helicobacter pylori (Hp) eradication plays a key role in the treatment and prevention of peptic ulcer diseases. Increasing clarithromycin resistance in Hp necessitates more effective treatments for eradication, such as bismuth‐containing quadruple therapy. We aimed to compare the safety and pharmacokinetics (PK) of bismuth between vonoprazan‐ and lansoprazole‐containing quadruple therapy in Hp‐positive subjects.

Methods

In this randomised, double‐blind, parallel‐group study, Hp‐positive subjects were randomised to receive vonoprazan‐ or lansoprazole‐containing quadruple therapy. Each subject received vonoprazan 20 mg or lansoprazole 30 mg combined with bismuth 220 mg, clarithromycin 500 mg and amoxicillin 1000 mg twice daily for 14 days. Blood sampling and urine collection for bismuth PK were conducted predose and up to 12 hours postdose at steady‐state. The PK parameters of bismuth were derived using a noncompartmental method and compared between treatments. An exploratory breath test for Hp was conducted at screening and at the follow‐up visit on day 42. Safety was assessed by adverse event monitoring, physical examinations, vital signs, 12‐lead electrocardiograms and clinical laboratory tests.

Results

A total of 30 subjects were randomised and 26 subjects completed the study (12 in the vonoprazan group and 14 in the lansoprazole group). The systemic exposure of bismuth in the 2 treatments was comparable (~5% difference). All subjects turned negative for Hp at the follow‐up visit. No significant difference in safety profiles was noted between the 2 treatments.

Conclusion

The systemic exposure of bismuth was similar between vonoprazan‐ and lansoprazole‐containing quadruple therapy. Vonoprazan‐containing quadruple therapy was safe and well tolerated.

Helicobacter pylori antimicrobial resistance in Melbourne, Australia. Time to review therapeutic guidelines?

BACKGROUND

Antimicrobial resistance (AMR) in Helicobacter pylori is a global concern. The AMR data to inform the Australian Therapeutic Guidelines is based upon data over 20 years old.

AIMS

To evaluate the frequency of antimicrobial resistance in H. pylori isolates from gastric biopsy specimens received in our laboratory in Melbourne, Australia To review the literature on resistance rates in Australia and compare historic data.

METHODS

A retrospective, observational study summarising AMR rates in all H. pylori isolates from our laboratory from 2015 to June 2020.

SETTING

Microbiology laboratory in metropolitan Melbourne, Australia, receiving referrals from private hospitals, gastroenterology clinics, and endoscopy suites.

OUTCOME MEASURES

Population minimum inhibitory concentration distributions and frequency of resistance to clarithromycin, amoxicillin, metronidazole, and tetracycline in H. pylori isolates.

RESULTS

386 H. pylori isolates with susceptibility testing data were identified. The frequency of resistance in this cohort was: clarithromycin 89.9%, amoxicillin 23.5%, metronidazole 66.1%, and tetracycline 4.4%. Comparison with historical data may suggest increasing AMR rates in Australia. Main limitation is lack of treatment history to correlate AMR results.

CONCLUSIONS

Definitive conclusions from this cohort cannot be made, but trends suggest rising levels of primary H. pylori AMR rates in Australia. This has important implications for empirical treatment decision making and treatment outcomes. Primary H. pylori AMR requires dedicated studies and current Australian therapeutic guideline recommendations may require re-evaluation. We propose considerations for improving the management of H. pylori in Australia. A centralised public health approach to H. pylori AMR surveillance should be established. This article is protected by copyright. All rights reserved.

Primary and secondary clarithromycin resistance in Helicobacter pylori and mathematical modeling of the role of macrolides

Clarithromycin is a macrolide antibiotic widely used for eradication of Helicobacter pylori infection, and thus resistance to this antibiotic is a major cause of treatment failure. Here, we present the results of a retrospective observational study of clarithromycin resistance (Cla-res) in 4744 H. pylori-infected patients from Central Hungary. We use immunohistochemistry and fluorescence in situ hybridization on fixed gastric tissue samples to determine H. pylori infection and to infer Cla-res status, respectively. We correlate this information with macrolide dispensing data for the same patients (available through a prescription database) and develop a mathematical model of the population dynamics of Cla-res H. pylori infections. Cla-res is found in 5.5% of macrolide-naive patients (primary Cla-res), with no significant sex difference. The model predicts that this primary Cla-res originates from transmission of resistant bacteria in 98.7% of cases, and derives from spontaneous mutations in the other 1.3%. We find an age-dependent preponderance of female patients among secondary (macrolide-exposed) clarithromycin-resistant infections, predominantly associated with prior use of macrolides for non-eradication purposes. Our results shed light into the sources of primary resistant cases, and indicate that the growth rate of Cla-res prevalence would likely decrease if macrolides were no longer used for purposes other than H. pylori eradication.

Clarithromycin is a macrolide antibiotic widely used for eradication of Helicobacter pylori infection. Here, Kocsmár et al. study clarithromycin resistance and previous macrolide consumption in 4,744 H. pylori-infected patients, shedding light into the sources of primary resistant cases and the role played by prior consumption of macrolides for non-eradication purposes.

Treatment of Refractory Helicobacter pylori Infection-Tailored or Empirical Therapy

The treatment of refractory Helicobacter pylori remains challenging in clinical practice. Factors that should be considered in the treatment of refractory H. pylori infection include treatment length, dosage of antibiotics and proton pump inhibitors (PPIs), number of drugs, and the selection of appropriate antibiotics. Extending the treatment length of triple therapy and non-bismuth quadruple therapy to 14 days may increase the eradication rate compared with a shorter period (7 or 10 days). The use of a higher dose of PPIs or vonoprazan may also increase the efficacy of triple therapy. Four-drug therapy, including bismuth or non-bismuth quadruple therapies, usually achieve higher eradication rates than triple therapy. The addition of bismuth or metronidazole to levofloxacin-amoxicillin-PPI therapy may also increase the eradication rate. Therefore, four-drug therapies containing a higher dose of PPIs for 14 days are recommended in the third-line treatment setting for refractory H. pylori infection. The selection of appropriate antibiotics may be guided by susceptibility testing or empirically by medication history. Tailored therapy guided by susceptibility testing or genotypic resistance is recommended whenever possible. However, properly designed empirical therapy based on prior medication history (i.e., avoid the reuse of clarithromycin or levofloxacin empirically) is an acceptable alternative to tailored therapy after considering accessibility, cost, and the preference of the patient.

Antibiotic Resistance of Helicobacter pylori Strains Isolated From Pediatric Patients in Southwest China

The number of antibiotics that are appropriate for Helicobacter pylori eradication in children is limited. Profiling regional or population-specific antibiotic resistance is essential in guiding the H. pylori eradication treatment in children. The aim of this study was to evaluate the antibiotic resistance in H. pylori strains isolated from children and adolescents in Southwest China. Gastric biopsies from 157 pediatric patients with or without previous H. pylori eradication treatment were collected for H. pylori culture. Susceptibility to amoxicillin (AML), clarithromycin (CLR), metronidazole (MTZ), levofloxacin (LEV), tetracycline (TET), furazolidone (FZD), and rifampicin (RIF) was determined by E-test or a disk diffusion assay. A total of 87 patients from three ethnic groups (Han/Tibetan/Yi) were H. pylori culture positive (55.4%). The overall resistance rates were 55.2% for CLR, 71.3% for MTZ, 60.9% for RIF, and 18.4% for LEV. No isolate was found to be resistant to AML, TET, and FZD. Among the 53 treatment-naïve pediatric patients, primary resistance rates to clarithromycin, metronidazole, levofloxacin, and rifampicin were 45.3, 73.6, 15.1, and 60.4%, respectively. Among the 34 treatment-experienced patients, secondary resistance rates to clarithromycin, metronidazole, levofloxacin, and rifampicin were 70.6, 67.6, 23.5, and 61.8%, respectively. Isolates exhibiting simultaneous resistance to clarithromycin and metronidazole were 28.3 and 52.9% among the treatment-naïve and treatment-experienced patients, respectively. In conclusion, among pediatric patients in Southwest China, resistance rates were high for clarithromycin, metronidazole, levofloxacin, and rifampicin, whereas nil resistance was found to amoxicillin, tetracycline, and furazolidone. Our data suggest that the standard clarithromycin-based triple therapy should be abandoned as empiric therapy, whereas the bismuth quadruple therapy (bismuth/PPI/amoxicillin/tetracycline) would be suitable as first-line empiric treatment regimen for this pediatric population. Tetracycline and furazolidone may be considered for treating refractory H. pylori infections in adolescent patients.